Association between clinical variables related to asthma in schoolchildren born with very low birth weight with and without bronchopulmonary dysplasia

ObjectiveTo assess the prevalence, spirometry findings and risk factors for asthma in schoolchildren who were very low birth weight infants with and without bronchopulmonary dysplasia.MethodsObservational and cross-sectional study. The parents and/or tutors answered the International Study of Asthma and Allergies in Childhood questionnaire. The schoolchildren were submitted to the skin prick test and spirometry assessment.Results54 schoolchildren who were very low birth weight infants were assessed and 43 met the criteria for spirometry. Age at the assessment (bronchopulmonary dysplasia=9.5±0.85; without bronchopulmonary dysplasia=10.1±0.86 years) and birth weight (bronchopulmonary dysplasia=916.7±251.2; without bronchopulmonary dysplasia=1171.3±190.5g) were lower in the group with bronchopulmonary dysplasia (p<0.05). The prevalence of asthma among very low birth weight infants was 17/54 (31.5%), being 6/18 (33.3%) in the group with bronchopulmonary dysplasia. There was an association between wool blanket use in the first year of life (p=0.026) with the presence of asthma at school age. The skin prick test was positive in 13/17 (76.5%) and 23/37 (62.2%) of patients with and without asthma, respectively. The schoolchildren with asthma had lower z-score values of forced expiratory flow between 25% and 75% of forced vital capacity (n=16;−1.04±1.19) when compared to the group of patients without asthma (n=27;−0.380.93) (p=0.049). There was no difference between the spirometry variables in the groups regarding the presence or absence of bronchopulmonary dysplasia.ConclusionsVery low birth weight infants with and without bronchopulmonary dysplasia showed a high prevalence of asthma (33.3% and 30.6%, respectively). Pulmonary flow in the small airways was lower in children with asthma.

ResumoObjetivoAvaliar prevalência, espirometria e fatores de risco para asma em escolares que foram recém-nascidos de muito baixo peso com e sem displasia broncopulmonar.MétodosEstudo observacional e transversal. Aplicou-se aos pais e/ou responsáveis o questionário International Study of Asthma and Allergies in Childhood. Foi feito teste cutâneo de hipersensibilidade imediata e espirometria nos escolares.ResultadosAvaliados 54 escolares que foram recém-nascidos de muito baixo peso e 43 preencheram critérios para espirometria. A idade na avaliação (displasia broncopulmonar=9.5±0,85; sem displasia broncopulmonar=10,1±0,86 anos) e o peso de nascimento (displasia broncopulmonar=9167±2512; sem displasia broncopulmonar=1171,3±1905g) foram menores no grupo com displasia broncopulmonar (p<0,05). A prevalência de asma entre os recém-nascidos de muito baixo peso foi de 17/54 (31,5%); no grupo com displasia broncopulmonar, de 6/18 (33,3%). Houve associação entre uso de cobertor de lã no primeiro ano de vida (p=0,026) com presença de asma na idade escolar. O teste cutâneo de hipersensibilidade imediata foi positivo em 13/17 (76.5%) e 23/37 (62,2%) nos grupos com e sem asma, respectivamente. Os escolares com asma apresentaram menores valores em z-score do fluxo expiratório forçado entre 25% e 75% da capacidade vital forçada (n=16;−1,04±1,19) comparados com os do grupo de pacientes sem asma (n=27;−0,38±0,93) (p=0,049). Não houve diferença entre as variáveis da espirometria no grupo com relação à presença ou não de displasia broncopulmonar.ConclusõesOs recém-nascidos de muito baixo peso, com e sem displasia broncopulmonar, apresentaram prevalência elevada de asma (33,3% e 30,6%, respectivamente). Os fluxos pulmonares das pequenas vias aéreas foram menores nos escolares com asma.